Perl, 43 bytes

Takes two strings with arbitrary content.
Returns merged result.

sub f{"@_"=~s/(.*)\K$"(?=\Q$_[1]\E$)\1//sr}

Inspired by Wezl's sed regex.

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posted 6 months ago

CC BY-SA 4.0

6mo ago

jhnc‭

591 reputation 0 46 59 98

Sed -E, 25 bytes

Takes second input, , comma, first input (inputs cannot contain , commas).

s/^(.*)(.*),(.*)\1$/\3\2/

posted over 5 years ago

CC BY-SA 4.0

Wezl‭

471 reputation 1 10 47 8

APL(Dyalog Unicode), 26 bytes ^SBCS

{⊃x/⍨⊃¨⍺∘⍷¨x←,∘⍵¨(⊂⍬),,\⍺}

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A dfn submission which takes the inputs as left and right argument.

I took way too long to come up with this. Fun challenge.

posted over 5 years ago

CC BY-SA 4.0

Razetime‭

3000 reputation 42 65 335 83

BQN, 18 bytes^SBCS

{⊑(⊑𝕨⊸⍷)¨⊸/∾⟜𝕩¨↑𝕨}

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A direct translation of Razetime's APL solution (my attempted improvement ⊣∾{⊢´/𝕨⊸«⊸≡¨↑𝕩}↓⊢ turns out to be not at all correct).

The BQN solution is much shorter mainly because it has Prefixes (↑) built in. Being able to filter with ⊸/ (see Before) also helps a lot.

{⊑(⊑𝕨⊸⍷)¨⊸/∾⟜𝕩¨↑𝕨}  # Function with left argument 𝕨 and right argument 𝕩
               ↑𝕨   # All prefixes of 𝕨
           ∾⟜𝕩¨     # Append 𝕩 after each one
         ⊸/         # Filter by...
  (    )¨           #   On each string,
    𝕨⊸⍷             #     Where does 𝕨 appear as a substring?
   ⊑                #     But I only care if it's the first one
 ⊑                  # Then take the first

Put together, the pattern ⊑𝕨⊸⍷ tests if 𝕨 is a prefix of the argument.

posted over 5 years ago

CC BY-SA 4.0

Marshall Lochbaum‭

681 reputation 0 20 68 9

Japt -h, 13 12 9 bytes

à m+V kbU

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à m+V kbU     :Implicit input of strings U & V
à             :Combinations of U
  m           :Map
   +V         :  Append V
      k       :Filter elements that return falsey (i.e., 0)
       bU     :  First 0-based index of U
              :Implicit output of last element

posted about 5 years ago

CC BY-SA 4.0

5y ago

Shaggy‭

2491 reputation 4 140 252 188

Jelly, 13 bytes

W;;Ƥ@ḣL}¹⁼ʋƇḢ

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Takes the two strings as arguments in reverse order.

posted over 5 years ago

CC BY-SA 4.0

5y ago

xigoi‭

91 reputation 0 3 9 2

Python 3, 82 81 bytes

lambda a,b:[a[:i]+b for i in range(len(a)+2)if i>len(a)or b[:len(a)-i]==a[i:]][0]

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posted about 5 years ago

CC BY-SA 4.0

5y ago

bastolski‭

181 reputation 0 6 18 2

JavaScript, 50 bytes

Assumes, per the test cases, that no RegEx characters will be included in the input. Otherwise, replace search with indexOf.

a=>g=(b,s=n=``)=>(s+b).search(a)?g(b,s+a[n++]):s+b

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posted 6 months ago

CC BY-SA 4.0

6mo ago

Shaggy‭

2491 reputation 4 140 252 188

Vyxal, 1 byte

⋎

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Builtin be like

posted about 5 years ago

CC BY-SA 4.0

emanresu A‭

411 reputation 0 19 41 6

Ruby, 40 bytes

f=->a,b{b.index(a)==0?b:a[/./m]+f[$',b]}

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If we could assume that string contains only letters and numbers (or to be more specific, no characters like \t\n\v\f\r \#$()*+-.?[\\]^{|}) then it could be improved to 36 bytes:

f=->a,b{b=~/^#{a}/?b:a[/./]+f[$',b]}

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posted over 4 years ago

CC BY-SA 4.0

4y ago

radarek‭

249 reputation 0 31 24 42